The pharmaceutical effect of a drug that has a specific pharmaceutical activity and therefore expresses an effect of curing a disease of a type results from the specific binding of the drug to the protein that participates in the pharmaceutical phenomenon to carry the disease and from the effect of the drug caused by it to specifically modify the function of the protein.
Therefore, when a drug for curing a disease specifically binds to a protein to modify its function in tissues or cells that exhibit the disease, then the protein participates in the disease, and it is a useful target for development of new medicines for the disease.
For example, an immunosuppressor FK506 is used as a medicine for transplantation and chronic inflammations. Professor Schreiber et al. have clarified that the specific binding protein in the diseases to which the medicine is directed is FKBP12 protein (Harding M W, Galat A. Uehling D E, Schreiber S L, Nature 341, pp. 758-760 (1989)). It has been further clarified that, after FK506 has bound to FKBP12, this further binds to calcineurin to express its immunosuppressive effect (Liu J, Farmer J D Jr, Lane W S, Friedman J, Weissman I, Schreiber S L, Cell 66(4), pp. 807-815 (1991)). Specifically, FKBP12 discovered by the use of FK506 and its immunoregulation route are important targets for further development of additional immunosuppressors.
The novel 35 kd protein of the invention binds to a substance WF00144 (FIG. 1). The substance WF00144 is a pharmaceutically active substance produced by fungi, Phoma sp. No. 00144. This substance inhibits in-vitro sugar production in primary-culture liver cells. In addition, the substance has hypoglycemic effect in diabetes model animals. Specifically, the substance is a medicine for diabetes, which inhibits sugar production in livers and expresses hypoglycemic effect (WO99/61645).
For the two reasons mentioned above, it is believed that the protein to which the substance WF00144 specifically binds may be useful for clarifying some new mechanism for development of diabetes and for developing novel medicines for diabetes. Prior to the present invention, however, no one knows such a protein capable of specifically binding to the substance WF00144.